我使用jsoup来解析html页面并提交表单。我需要在提交表单之前删除“后退”按钮。我使用 element.remove() 方法，但后来我发现 form.formData() 没有改变。请求的元素已从 form.children() 中删除，但存在于 form.elements() 中。这是一个错误还是我使用了错误的方法从表单中删除元素？
public class JsoupCheck {
public static void main(String[] args) {
String html = "<html><body><form action=\"demo\">"
+ "<input type=\"submit\" name=\"buttonSave\" value=\"Save\">"
+ "<input type=\"submit\" name=\"buttonBack\" value=\"Back\">"
+ "<select name=\"selection\">"
+ " <option value=\"value1\">Value 1</option>"
+ " <option value=\"value2\" selected>Value 2</option>"
+ " <option value=\"value3\">Value 3</option>"
+ "</select>"
+ "</form></body></html>";
Document doc = Jsoup.parse(html);
FormElement form = (FormElement) doc.select("form").first();
Element e = form.select("form").first();
System.out.println("=== Original content of form");
System.out.println(e);
System.out.println("=== Original content of form.formData()");
for (Connection.KeyVal i : form.formData()) {
System.out.println(i.key() + "=" + i.value());
}
System.out.println("form.elements().size() = " + form.elements().size());
System.out.println("form.children().size() = " + form.children().size());
e.select("input[name=buttonBack]").remove();
System.out.println();
System.out.println("=== Content of form after remove buttonBack (result: buttonBack removed)");
System.out.println(e);
System.out.println("=== Content of form.formData() after remove buttonBack (result: buttonBack exist)");
for (Connection.KeyVal i : form.formData()) {
System.out.println(i.key() + "=" + i.value());
}
System.out.println("form.elements().size() = " + form.elements().size());
System.out.println("form.children().size() = " + form.children().size());
}
}
输出是:
=== Original content of form
<form action="demo">
<input type="submit" name="buttonSave" value="Save">
<input type="submit" name="buttonBack" value="Back">
<select name="selection"> <option value="value1">Value 1</option> <option value="value2" selected>Value 2</option> <option value="value3">Value 3</option></select>
</form>
=== Original content of form.formData()
buttonSave=Save
buttonBack=Back
selection=value2
form.elements().size() = 3
form.children().size() = 3
=== Content of form after remove buttonBack (result: buttonBack removed)
<form action="demo">
<input type="submit" name="buttonSave" value="Save">
<select name="selection"> <option value="value1">Value 1</option> <option value="value2" selected>Value 2</option> <option value="value3">Value 3</option></select>
</form>
=== Content of form.formData() after remove buttonBack (result: buttonBack exist)
buttonSave=Save
buttonBack=Back
selection=value2
form.elements().size() = 3
form.children().size() = 2
最佳答案
FormElement 是一种特殊类型的节点。除了维护所有子元素的列表(继承自 Node)之外，它还保存表单内所有元素的第二个内部列表。
public class FormElement extends Element {
private final Elements elements = new Elements();
...
}
当您对子级调用 Node#remove 时，它会更新父级的子级列表，而不是内部列表。
因此，要真正删除一个元素，您还需要将其从这个内部列表中删除:
e.select("input[name=buttonBack]").remove();
form.elements().removeIf(e -> e.attr("name").equals("buttonBack"));
关于java - JSoup:如何从表单中删除元素？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/46482697/